It is frequently desirable for particular applications and uses to provide a container having a cover which is movable toward and away from the bottom of the container. Generally, in order to provide access to the interior of such a container, the cover is moved away from the container bottom to expose openings in the sidewall of the container or to completely open the top of the container.
Various techniques have been developed to achieve movement of the cover relative to the container bottom. One technique involves the utilization of mating threaded members carried by the lid and the container bottom, respectively (see, for instance, U.S. Pat. No. 4,361,279). The provision of threaded members is disadvantageous because the required threads are difficult to manufacture. In addition to complicating the assembly of the container by requiring the manual application of the lid to the container bottom, the threaded members also complicate the opening of the containers by requiring the use of two hands: one hand to hold the bottom of the container stationary and the other hand to rotate the lid relative to the container bottom.
Another technique involves the use of a telescoping or sliding type of engagement between the lid and the bottom of the container (see, for instance, U.S. Pat. Nos. 2,765,950; 2,765,951 and 3,286,872). These containers, like the containers described above which utilize threaded members, require the use of two hands to open them: one hand to hold the bottom of the container and the other hand to push or pull the lid so that it moves toward or away from the container bottom.